A higher injection pressure and new volume control system has improved power and torque figures for BMW 330d’s uprated turbodiesel powerplant.

A higher injection pressure and new volume control system has improved power and torque figures for BMW 330d’s uprated turbodiesel powerplant.

BMW South Africa last week introduced a host of specification changes to the 2003 model year 3-Series, one of which was an update to the 330d’s powerplant.

According to the manufacturer, BMW’s three-litre six-cylinder turbodiesel engine now has a peak power output of 150 kW at 4 000 r/min (up from 135 kW) and maximum torque of 410 N.m from 1 500 to 3 000 r/min (up from 390 N.m).

Compared with its predecessor, the new 330d is claimed to accelerate from zero to 100 km/h in 7,2 seconds (up from 7,4) and has a faster top speed of 242 km/h (previously 235 km/h). Acceleration from 80 to 120 km/h in fourth gear reportedly takes 6,1 seconds.

In addition, the new 330d is claimed to consume 6,6 litres of diesel per 100 km in the New European Driving Cycle (NEDC).

With maximum sys­tem pressure increasing from 1 350 to 1 600 bar, fuel is injected more quickly and atomised more efficiently and, in doing so, develops more power and enhances fuel economy, a BMW SA spokesman was quoted as saying.

A further point is that volume control limits the amount of fuel compressed to maximum pressure, tailoring the compression process to the amount required by the en­gine at any given point in time. The reduction of energy consumed by the high-pressure pump as a consequence also helps to reduce the amount of fuel consumed in the compression cycle.

Fuel is injected up to four times per working cycle, and according to the manufacturer, double-pilot fuel injection results in a softer combustion process and after-injection improves particle oxidation and reduces harmful emissions.

BMW’s engineers have also refined the tur­bo­charger’s variable turbine geometry. The turbine blades are made of stronger material than its predecessor, and there have been improvements to the efficiency of both the turbine and the compressor. BMW has further developed a new intercooler.

To make optimum use of the latest generation of common rail technology and the options it offers, the software of BMW’s DDE5 Digital Diesel Elec­tronics has been adapted to the new engine of the 330d. DDE5 has computer capacity up by a factor of 10. It features 32-bit architecture, a 1,5-megabyte memory, and operates with a cycle frequency of 40 megahertz.

Original article from Car